BorderCrossing 

When two people get together and align ass holes together. One of the two people begin to defecate. (this person is normally referred to as the "Mexican") The shit eventually crosses into the other person if it is stiff enough. (the one who is taking the blow is normally referred to as the "Trump Supporter")

"bro, lets do some good old fashioned BorderCrossing"
"Nah bro, I'm a Hillary supporter"

BorderCrossing by Icycold September 23, 2016

Southern border crossing 

Where two guys are going down on the same girl and one is eating the pussy and one is eating the ass and then they kiss

Me and my buddy did a southern border crossing on Maria after the party last night.

Southern border crossing by A 1969 Honda civic October 14, 2023

El Paso Border Crossing 

A sex act consisting of a rim-job performed through a chain-link fence. This is one part of the {El Paso Roundup}.

The girl ran out of gas on the highway and is willing to give an El Paso Border Crossing in return for some gasoline.

El Paso Border Crossing by Choochfactor June 3, 2018